The management and tracking of entities, such as personnel, assets, and other objects, is performed in a wide variety of environments and is often cumbersome, labor intensive, and expensive. Radio receivers and transmitters have been used to identify personnel and objects in such environments. For example, various systems are known for attaching radio frequency identification (RFID) tags to entities, such as personnel, assets, and automobiles. When automobiles equipped with radio tags enter a certain area, such as a toll booth area, the automobiles are automatically identified. The appropriate tolls are deducted from corresponding accounts, thereby eliminating the need for drivers to stop and make payments at toll booths. When radio tags are placed on personnel, they can be automatically identified and checked for authorized entry to a facility in a security application called access control. Assets which are tagged can be identified and tracked as they move throughout a facility for the purposes of automatically locating them. They can also be automatically counted therefore providing inventory control. They can also be protected as when an asset approaches an exit doorway the system can automatically determine if the asset is authorized to be removed from the facility. Tagged vehicles, assets, and personnel can be linked logically in the system to enable greater visibility and control.